From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47141) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1evlxV-0005fK-O6 for qemu-devel@nongnu.org; Tue, 13 Mar 2018 11:35:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1evlxP-0005sb-Rw for qemu-devel@nongnu.org; Tue, 13 Mar 2018 11:35:25 -0400 From: Peter Maydell Date: Tue, 13 Mar 2018 15:34:58 +0000 Message-Id: <20180313153458.26822-10-peter.maydell@linaro.org> In-Reply-To: <20180313153458.26822-1-peter.maydell@linaro.org> References: <20180313153458.26822-1-peter.maydell@linaro.org> Subject: [Qemu-devel] [PATCH 9/9] hw/arm/raspi: Provide spin-loop code for AArch64 CPUs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-arm@nongnu.org, qemu-devel@nongnu.org Cc: patches@linaro.org, Pekka Enberg , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Andrew Baumann The raspi3 has AArch64 CPUs, which means that our smpboot code for keeping the secondary CPUs in a pen needs to have a version for A64 as well as A32. Without this, the secondary CPUs go into an infinite loop of taking undefined instruction exceptions. Signed-off-by: Peter Maydell --- hw/arm/raspi.c | 41 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) diff --git a/hw/arm/raspi.c b/hw/arm/raspi.c index ae15997669..06f1e08ca9 100644 --- a/hw/arm/raspi.c +++ b/hw/arm/raspi.c @@ -27,6 +27,7 @@ #define BOARDSETUP_ADDR (MVBAR_ADDR + 0x20) /* board setup code */ #define FIRMWARE_ADDR_2 0x8000 /* Pi 2 loads kernel.img here by default */ #define FIRMWARE_ADDR_3 0x80000 /* Pi 3 loads kernel.img here by default */ +#define SPINTABLE_ADDR 0xd8 /* Pi 3 bootloader spintable */ /* Table of Linux board IDs for different Pi versions */ static const int raspi_boardid[] = {[1] = 0xc42, [2] = 0xc43, [3] = 0xc44}; @@ -63,6 +64,40 @@ static void write_smpboot(ARMCPU *cpu, const struct arm_boot_info *info) info->smp_loader_start); } +static void write_smpboot64(ARMCPU *cpu, const struct arm_boot_info *info) +{ + /* Unlike the AArch32 version we don't need to call the board setup hook. + * The mechanism for doing the spin-table is also entirely different. + * We must have four 64-bit fields at absolute addresses + * 0xd8, 0xe0, 0xe8, 0xf0 in RAM, which are the flag variables for + * our CPUs, and which we must ensure are zero initialized before + * the primary CPU goes into the kernel. We put these variables inside + * a rom blob, so that the reset for ROM contents zeroes them for us. + */ + static const uint32_t smpboot[] = { + 0xd2801b05, /* mov x5, 0xd8 */ + 0xd53800a6, /* mrs x6, mpidr_el1 */ + 0x924004c6, /* and x6, x6, #0x3 */ + 0xd503205f, /* spin: wfe */ + 0xf86678a4, /* ldr x4, [x5,x6,lsl #3] */ + 0xb4ffffc4, /* cbz x4, spin */ + 0xd2800000, /* mov x0, #0x0 */ + 0xd2800001, /* mov x1, #0x0 */ + 0xd2800002, /* mov x2, #0x0 */ + 0xd2800003, /* mov x3, #0x0 */ + 0xd61f0080, /* br x4 */ + }; + + static const uint64_t spintables[] = { + 0, 0, 0, 0 + }; + + rom_add_blob_fixed("raspi_smpboot", smpboot, sizeof(smpboot), + info->smp_loader_start); + rom_add_blob_fixed("raspi_spintables", spintables, sizeof(spintables), + SPINTABLE_ADDR); +} + static void write_board_setup(ARMCPU *cpu, const struct arm_boot_info *info) { arm_write_secure_board_setup_dummy_smc(cpu, info, MVBAR_ADDR); @@ -99,7 +134,11 @@ static void setup_boot(MachineState *machine, int version, size_t ram_size) /* Pi2 and Pi3 requires SMP setup */ if (version >= 2) { binfo.smp_loader_start = SMPBOOT_ADDR; - binfo.write_secondary_boot = write_smpboot; + if (version == 2) { + binfo.write_secondary_boot = write_smpboot; + } else { + binfo.write_secondary_boot = write_smpboot64; + } binfo.secondary_cpu_reset_hook = reset_secondary; } -- 2.16.2